Unable to build on Win10

```
julia> Pkg.build("CLBLAS")
INFO: Building CLBLAS
INFO: Attempting to Create directory C:\Users\luyao\.julia\v0.5\CLBLAS\deps\downloads
INFO: Downloading file https://github.com/clMathLibraries/clBLAS/releases/download/v2.12/clBLAS-2.12.0-Windows-x64.zip
INFO: Done downloading file https://github.com/clMathLibraries/clBLAS/releases/download/v2.12/clBLAS-2.12.0-Windows-x64.zip
INFO: Attempting to Create directory C:\Users\luyao\.julia\v0.5\CLBLAS
INFO: Directory C:\Users\luyao\.julia\v0.5\CLBLAS already created

7-Zip [64] 9.20 Copyright (c) 1999-2010 Igor Pavlov 2010-11-18

Processing archive: C:\Users\luyao\.julia\v0.5\CLBLAS\deps\downloads\clBLAS-2.12.0-Windows-x64.zip

Extracting package
Extracting package\bin
Extracting package\bin\blasPerformanceTesting.py
Extracting package\bin\clBLAS-client.exe
Extracting package\bin\clBLAS-tune.exe
Extracting package\bin\clBLAS.dll
Extracting package\bin\errorHandler.py
Extracting package\bin\make-ktest.exe
Extracting package\bin\measurePerformance.py
Extracting package\bin\performanceUtility.py
Extracting package\bin\plotPerformance.py
Extracting package\bin\test-correctness.exe
Extracting package\bin\test-functional.exe
Extracting package\bin\test-medium.exe
Extracting package\bin\test-short.exe
Extracting package\bin\testPerfWrapper.exe
Extracting package\CMake
Extracting package\CMake\clBLASConfig.cmake
Extracting package\CMake\clBLASConfigVersion.cmake
Extracting package\CMake\clBLASTargets-release.cmake
Extracting package\CMake\clBLASTargets.cmake
Extracting package\include
Extracting package\include\clAmdBlas.h
Extracting package\include\clAmdBlas.version.h
Extracting package\include\clBLAS-complex.h
Extracting package\include\clBLAS.h
Extracting package\include\clBLAS.version.h
Extracting package\lib64
Extracting package\lib64\import
Extracting package\lib64\import\clBLAS.lib

Everything is Ok

Folders: 6
Files: 24
Size: 34073671
Compressed: 4886063
===============================================================[ ERROR: CLBLAS ]================================================================
LoadError: Provider BinDeps.Binaries failed to satisfy dependency libCLBLAS
while loading C:\Users\luyao\.julia\v0.5\CLBLAS\deps\build.jl, in expression starting on line 44

================================================================================================================================================
================================================================[ BUILD ERRORS ]================================================================
WARNING: CLBLAS had build errors.

- packages with build errors remain installed in C:\Users\luyao\.julia\v0.5
- build the package(s) and all dependencies with `Pkg.build("CLBLAS")`
- build a single package by running its `deps/build.jl` script

================================================================================================================================================
```